Basic Definitions and Overview About different types of data models
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Added: Mar 24, 2015
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All Data models in DBMS
Overview Data Information Database Data Model Types of Data Model Record Base model Relationship model Network Model Hierarchical Model 2.Entity Relationship Model 3.Object-Oriented Model Prepared By Amad Ahmad BSSE 5th Semester Abasyn University Peshawar 2
A data is known as the row fact which is stored in computers memory and used by the user as the output. Example-21. Data
Information Collection of data its called information. Example-House no 21C-S-1,Sch No 78 Indore
Database A collection of inter related data its called database.
Data Model A data model is a collection of concepts that can be used to describe the structure of a database.
Types of Data Models 1.Record Base model Prepared By Amad Ahmad BSSE 5th Semester Abasyn University Peshawar 7
Types of Data Models 1.Record Base model A record based data model is used to specify the overall logical structure of the database. Each record type defines a fixed no. of fields having a fixed length. Prepared By Amad Ahmad BSSE 5th Semester Abasyn University Peshawar 8
Relational model In the relational model, data is organized in two-dimensional tables called relations. Prepared By Amad Ahmad BSSE 5th Semester Abasyn University Peshawar 9
Relations No Course-Name Unit CIS15 Intro to C 5 CIS17 Intro to Java 5 CIS19 UNIX 4 CIS51 Networking 5 Attributes Tuples Prepared By Amad Ahmad BSSE 5th Semester Abasyn University Peshawar 10
Attributes. Each column in a relation is called an attribute. Relations Tuples Each row in a relation is called a tuple. A tuple defines a collection of attribute values. Prepared By Amad Ahmad BSSE 5th Semester Abasyn University Peshawar 11
Network Model In the network model, the entities are organized in a graph, in which some entities can be accessed through several paths No Name ID Name Course No Name Unit ID Name DEPARTMENT COURSES STUDENTS PROFESSORS Prepared By Amad Ahmad BSSE 5th Semester Abasyn University Peshawar 12
Hierarchical Model The hierarchical data model organizes data in a tree structure
PROFESSORS No Name ID Name Course No Name Unit ID Name DEPARTMENT COURSES STUDENTS Hierarchical Model Prepared By Amad Ahmad BSSE 5th Semester Abasyn University Peshawar 14
2.Entity Relationship Model The E-R (entity-relationship) data model views the real world as a set of basic objects (entities) and relationships among these objects ER Model Basics Entity Entity Set Attributes Relationship Prepared By Amad Ahmad BSSE 5th Semester Abasyn University Peshawar 15
Entity entity is a thing in the real world with an independent existance. and entity set is collection or set all entities of a particular entity type at any point of time. Prepared By Amad Ahmad BSSE 5th Semester Abasyn University Peshawar 16